Video and slides synchronized, mp3 and slide download available at URL http://bit.ly/2QbJBsd. Trisha Gee talks about Java 8, wondering whether we should move to a later version, which one to choose, what sorts of issues we might run into if we do choose to upgrade, and how the support and license changes that came in with Java 11 might impact us. Filmed at qconlondon.com. Trisha Gee has developed Java applications for a range of industries, including finance, manufacturing, software and non-profit. She has expertise in Java high performance systems, is passionate about enabling developer productivity, and dabbles with Open Source development. As a Developer Advocate for JetBrains, she gets to share all the interesting things she’s constantly discovering.

2. InfoQ.com: News & Community Site
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java-8-plus
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3. Purpose of QCon
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Strategy
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Highlights
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Presented at QCon London
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4. Upgrading Past Java 9 Sounds Scary
…and I don’t want to pay for Java

5. Super happy with Java 8, thanks

14. Starting with Java 11, Oracle will provide JDK releases
under the open source GNU General Public License v2,
with the Classpath Exception (GPLv2+CPE), and under a
commercial license for those using the Oracle JDK as
part of an Oracle product or service, or who do not wish to
use open source software. This… replaces the historical
“BCL” license, which had a combination of free and paid
commercial terms.
Donald Smith, Sr. Director of Product Management (June 2018)
https://blogs.oracle.com/java-platform-group/oracle-jdk-releases-
for-java-11-and-later

15. That sounds frightening, and overly
complicated. Talk us through it.
The Lego Batman Movie

16. That sounds frightening, and overly
complicated. Talk us through it.
The Lego Batman Movie

17. https://flic.kr/p/8xhk74

18. From Java 11 forward, Oracle JDK builds
and OpenJDK builds will be essentially identical.
Donald Smith, Sr. Director of Product Management (Sept 2018)
https://blogs.oracle.com/java-platform-group/oracle-jdk-releases-
for-java-11-and-later

19. https://blog.joda.org/2018/09/time-to-look-beyond-oracles-jdk.html

22. https://adoptopenjdk.net

23. https://adoptopenjdk.net/support.html

25. Language features

26. JShell

27. JShell

28. JShell

29. var

30. var

31. var

32. var

33. var

34. var

35. Convenience Factory Methods for Collections

36. Convenience Factory Methods for Collections

37. Convenience Factory Methods for Collections

38. Convenience Factory Methods for Collections

39. Collecting to Unmodifable Collections
items.stream()
.filter(Objects::nonNull)
.map(Object::toString)
.collect(Collectors.toUnmodifiableList());

40. New Methods on Stream API
items.stream()
.takeWhile(user -> user.count() < maxCount)
.forEach(user -> position.incrementAndGet());

41. Predicate.not()

42. New Methods on Optional

43. Http Client
@tddmonkey

44. Multi Release Jar Files

45. Jigsaw

46. Java Module System

47. Java Module System

48. JLink

49. And in the future?

50. Java 12: Switch expressions

51. • JEP 302: Lambda Leftovers (including underscore for
param)
• JEP 305: Pattern Matching (Preview)
• Data Classes for Java
• Project Amber
• Valhalla
• Loom
And in the future?

53. Performance

54. Memory Usage

55. • Java 9: JEP 248: G1 the Default GC
• Java 10: JEP 307: Parallel Full GC for G1
• Java 11: JEP 318: Epsilon (Experimental)
• Java 11: JEP 333: ZGC (Experimental)
Garbage Collectors

56. • Java 9: JEP 248: G1 the Default GC
• Java 10: JEP 307: Parallel Full GC for G1
• Java 11: JEP 318: Epsilon (Experimental)
• Java 11: JEP 333: ZGC (Experimental)
• Java 12: JEP 189: Shenandoah (Experimental)
• Java 12: More Updates to G1
• Java 12: More Improvements to ZGC
Garbage Collectors

57. Cost
£$€

58. Catch the 6 month release train

59. If It Hurts, Do It More Frequently,
and Bring the Pain Forward
An idea from Extreme Programming (XP)
Continuous Delivery – Jez Humble & Dave Farley

61. Modularity?

62. Missing classes / methods

64. Run on updated JDK
It might “just work”

65. Address compiler warnings
…they are there for a reason

66. Update your dependencies
And add new ones

67. Update your build tool
Maven and Gradle work with Java 12

68. Compile against updated JDK
…and start using the shiny new features

70. Java Is Changing
…fast

71. Modern Java Can Help You
Performance, cost, maintenance…

72. Upgrade Now And Reduce Future
Pain
…and keep upgrading, at least in CI

74. Watch the video with slide
synchronization on InfoQ.com!
https://www.infoq.com/presentations/
java-8-plus